Illegal HW instructions on x86-64 Linux while HW is not available

Hi there, my code is:

```rust
pub fn main(){
    unsafe {
        let mut err = 0;
        opusic_sys::opus_encoder_create(48000, 1, 2048, &mut err);
    }
}
```

![image](https://user-images.githubusercontent.com/23637939/86390015-eec60c00-bc9f-11ea-973e-16d930172daa.png)

(Illegal instruction, Core dumped)
